Oil engine



Nov. 17, 1925- 1,561,913

c, L. cUMMms OIL ENGINE Filed July so 1924 Patented Nov. 17, 1925.

UNITED STATES PATENT I OFFICE CLESSIE L. CUMMINS. OF COLUMBUS, INDIANA. ASSIGNOR TO OIL ENGINE DEVELOP- MENT COMPANY, 0F COLUMBUS,.INDIANA. A CORPORATION OF INDIANA.

OIL ENGINE.

Application illed J'uly 30, 1924. Serial No. 729,143.

To all whom 1f-may concern:

Be it known that I, CLEssIE L. CUMMiNs, a citizen of the United States, residing at Columbus, in the county of Bartholomew '2 and State of'Indiana, have invented certain newand useful Improvements in' Oil Engines, of'which the following is a specification.

This invention relates to oil burning engines of the general ty e wherein the fuel is burned by the heat o the air compressed by the piston within the combustion chamber of the cylinder.

The principal object of my invention is lto provide an oil burning engine which eliminatesv or overcomes many of the objections to, and defects in oil burning engines of those types in which thel charge of oil is injected into the combustion chamber by f a blast o compressed air delivered from an external source, as in the well-known Diesel engine, or in which the charge is injected into the combustion space by a preliminary explosion in an auxiliary chamber, as in the well vknown I-Ivid or Brons engines, or in which vpart or all of the fuel charge is ejected-in liquid form directly into the coinbustion space by mechanical means, while at the same time `my engine will possess many of the advantages of sucli types of enginesand be more simple in design, more efficient and economical 1n operation, capable of developing hi h power, possessed of a marked degree o flexibility, and free from carbon troubles.

lVitliv the above and incidental objects in view, `the invention consists in certain novel features of construction and combination vof parts, the 'essential elements whereof are recited in the appended claims, vand preferred and modified forms of embodiment of which are described in detail hereinafter and illustrated in full in the accompanyin jdrawings, which form part of this speci cation.

Of said drawings, Fig.A 1 isla vertical fragmentary section taken through the u per part of a four-cycle engine showing t e preferred form of embodiment of my invention applied thereto;'Fig. 2 is a bottom plan view ofthe inner cup-shaped member section through an injector embodying va modified form of my invention.

Fig. 1 illustrates, in section, the upper part of a cylinder 6 and reciprocating piston 7 of a four-cycle engine, to which, for the pur oses of illustration, I have shown the pre erred form of embodiment of my invention applied. An air intake valve 8 and an exhaust valve 9 may be of any approved construction.

The fuel injector, in general, comprises a body member or lug 10, an injecting plunger 11, operable 1n the central bore 11 of the plug, a cup-shaped member 12 litting over and about the lower end of the plug 10, a second cup-sha ed member 13 of generally similar shape, tted over the inner cup-shaped member 12, anda fuel inlet -valve 14 mounted in a bore 15 in the plug. The lower end of the central bore inthe plug is closed by the lower conical end of the cup 12 so that when the plunger 11 1s retracted or elevated to the position illustrated in Fig. l an atomizing or Vaporizing chamber 16 is formed under the plunger 11'. The bottom of this chamber, formed by the cup 12,' is conical and of the -saine contour as the lower conical end' of the plunger 11, to lform a seat for this conical end, and the apex 'of the conical e seat is provided with a very shallow opening 17 into which the pointed end f the plunger 11 projects when the latter is in its lowered position. The lower or bottom lface of the conical end of the cup 12, as

best shown in Fig. 2, is provided with a centrally-located circular rotrudin portion 18 having grooves 19 t erein ra iating outwardly from the central opening 17, so that an annular oil space 20 around the cylinder, is provided with very restricted passages or openings 21 communica.

with the combustion chamber and radiating outwardly from the. central o ening 17.

The lwerend of the fuelp inlet valve 'ido 14 is pointed and is adapted to close the upper end of a conduit 22 leading to the annular space 20 and a large groove 20' in the bottom of the cup member 12.

I have not shown in detail in the drawings operating means for actuating the ejeeting plunger 11 and the fuel valve 14, as any desire -or approved form of devices may be used. The arms 26 and 27, shown diagrammatically in dotted lines, may be considered as forming parts of the operating mechanisms for the plunger and valve respectively.

In the modified form of my invention, shown in Fig. 3, the lower end of the plunger 11 has a concaved seat which may be spherical as shown, or conical, if desired. But one cup member 23 is employed and it is provided with a convex seat 24 which may be spherical as shown, or conical if the lower end of the plunger 11 is provided with a concave conical end. The radiating distributing openings 2l open into the vaporizing chamber 16 adjacent the edge of the seat 24 and are preferably arranged tangential to this seat. The fuel conduit 22 extends through the lower end of the cup member 23 and opens at the center of the seat 24 and upwardly into the vaporizing chamber 16.

The operation of the preferred form of my invention is as follows: During the suetion stroke of the piston 7, air is drawn into the cylinder past the air inlet valve 8. During this same stroke, the fuel valve l14 is elevated by its operating mechanism to unseat its lower end and a charge of fuel, forced either by gravity or by a pump or other suitable means, flows'through the oil conduit 22 into the annular chamber 20 and the radiating passages 19. This flow of the charge forces the charge of oil already in such space and passages into the pointed end of the vaporizing chamber 16. This charge, which is deposited in the vaporizing chamber, has stood in the annular chamber 20 and the passages 19 from the time it was deposited therein during the preceding suction stroke. Each charge of fuel, when it is deposited in the annular space 20 and the grooves 19. serves to cool the pointed projecting end of the injector, and hence prevents it from getting so hot as to cause pre ignition, or cause a deposit of carbon thereon, and at the same time the absorption of the heat by the charge heats the oil and makes it more easil and thoroughly vaporizable. From the eginning of the period when the liquid charge is deposited in the lower end of the vaporizing chamber until after the beginningr but near the initial part of the compression stroke of the piston, I preferably slowly elevate the plunger 11 from its lowermost position to its retracted position, shown in Fig 1, so as to create a partial vacuum in the vaporizing chamber 16 for the purpose of )reventin the partial vacuum in the com ustion ciamber from causing any of the liquid fuel to drip or be drawn into the combustion chamber. I find that this is a very im or'tant feature. The plunger 11 is then hel in retracted position during the remainder of the compression stroke, and during such stroke part of the heated air, compressed in the combustion chamber and heated due to its compression, is forced to flow throu h the openin 21 into the vaporizing c iamber 16. 'Ishese streams of highly compressed heated air rushin through the openings 21 sweep throug the heated oil in the lower end of the vaporizing chamber 16 with the result that the oil is entrained with the air and thoroughly mixed, atomized, and vaporized with it in the vaporizing. chamber 16. Near the beginning of the power stroke of the piston, the plunger 11 is rapidly advanced or de ressed until its lower end is firmly seate and during this movement of the plunger the dry gaseous mixture of fuel and air is rapidly forced out of the chamber 16 through vthe restricted radiatin f openings 21 into the combustion chamber o the cylinder. As this dry gaseous charge is injected into the combustion chamber it ignites or explodes, thereby greatly increasing the pressure in the combustion chamber, driving the piston downwardly.

l find it is very important that the charge of liquid fuel be dischar ed into the injector at a point where it will be swept by and entrained with the compressed air entering the vaporizihg chamber rather than be discharged at a point remote from the seat, else some or all of the fuel is'not vaporized or equally distributed in the auxiliary chamber, with the result that some of it is injected into the combustion chamber in a liquid condition with accompanying deleterious results, such as extremely momentary high pressures, late combustion of part of the charge, decrease in power, deposit of carbon, and unequal distribution of the charge in the combustion' chamber. Then the plunger 11 is lowered, to in'ect the charge into the combustion cham er, the plunger is fully advanced so that its lower end is seated against the seat to insure the injection of all of the dry gaseous charge from the vaporizing chamber in order that the maximum efficiency may be obtained and the formation of carbon in the vaporizing chamber and the communicating restricted passages is prevented. I find that this is also an important desideratum of my invention, and with this in view the openings 21 are preferably madey as short and small as practical.

The operation of the modified form is substantially the saine as that of the preferred form, described above. The compressed air., during the compression stroke rushes through the openings 21 and sweeps through orl over the oil deposited on or .around the edge of the seat 24 with the result that the oil is thoroughly agitated land vaporized so that it forms with the heated air a dry gaseous mixture which is ejected in such form into the combustion space when the plunger 11 is lowered.

I claim:

1. In an oil engine, the combination of a cylinder and a piston operable therein,l a fuel vaporizing and injecting device comprising a chambervhaving restricted openings between it and the combustion s ace of the cylinder, a plunger operable in said chamber, means for discharging a charge of liquid fuel directly into said chamber' and at a point where it forms a vpool over said openings so that the charge of fuel is-heated, vaporized and mixed with the air forced from the combustion space into said chamber through said openings, and means for operating said plunger to eject the entire gasified mixture of air and fuelfrom 'said chamber through said communicating openings into said combustion space.-

2. In an oil engine, the combination of a cylinder and a piston operable therein, a

fuel vaporizing and injecting device having its discharge end subjected to the heat of combustion in the combustion space of the c linder. and comprising a chamber having s ort restricted radiating openings between it and the combustion space of the cylinder serving as the sole means through which air enters said-chamber, a plun er operable in said chamber, means for con ucting the liquid fuel through said heated end and discharging said li uid fuel into said chamber at a point direct y in the path of air forced by said piston from the combustion space through said openings so vthat the fuel is y vaporized and mixed with such air in said chamber, and -means for operating said plunger to eject the entire mixture of air and fuel from said chamber through said j short openin s into the combustion space.

3. In an oil engine, the combination of a cylinder and .a piston operable therein, a

fuel vaporizing and injectingv dvice :come

prising va chamber having restricted communicating means between it'and the combust-ion s ace of said cylinder, a lunger o rable 1n said chamber, means or disc arginglliquid fuel into said device at a int w 'ch is in the path ofthe air forced om said combustion space through said communicating meansso that the fuel is4 mixed with and thorou hly vaporized by the air forced'into said c amber, and means forretracting 'said plunger while the'fuel is 'being so deposited and subsequently advanc- .for retracting said plunger while the fuel is being so deposited and during the remainder of the suction stroke and -then advancing the plunger to eject the mixture of fuel and air from said chamber into the combustion s ace.

5. In an oil engine, the combination .of a cylinder and a piston operable therein, a

fuel vaporizing and injecting device com' prising a chamber having restricted communicating openings `between it and the combustion space of the cylinder, a plunger operable in said chamber, means for depositingliquid fuel at the discharge end of said chamber during the suction stroke of the v l iston so that the air forced b lthe piston rom the combustion space t rough said openings mixes with and vaporizes the fuel in said chamber, and means for retracting v said plunger while the fuel is being so deposited and for advancing said plunger to eject the entire mixture of fuel and air from said chamber into the combustion space during the combustion stroke of the engine.

6. In an oil engine, the combination of a cylinder and av piston operable therein, a fuel vaporizin and injecting device comprisin a chamer and a plunger operable in said c amber which has a seat at-its discharge end against which the end of the plunger seats when vfully advanced, the device also being provided with fuel-feeding and restricted passages for causin the fuel to enter said chamber through sai seat and the entire vaporized mixture of air and fuel to be ejected from said chamber through the restricted passages into the combustion space with a central opening at its discharge end and a plunger having a conical end to seat against sai conical seat when the ,plunger is fully advanced, the device also bei provided with fuel-feeding and restric passages eommunicating with said opening Vforcansing the fuel. to enter saidchamber throughsaid opening and the va rized mixture of air and fuelto be ejec from said chamber through the restricted passages into the combusti-on ace of the cylinder by the advance ofsai plunger to said seat,-and means for retracting and advancing said plunger.

8. In an oil enginethe combination of a cylinder and a piston operable therein, a

- fuel vaporizing and injecting device having its inner end projecting into the combustion space of the cylinder so that it is subjected to the heat of combustion in the combustion space and also having a chamber with restricted communicating means between it and thevcombustion space, and oil feeding conduit means extending through said heated end for depositing a charge of oil at a point in thev path of the air fborced by said piston from the combustion space through said restricted communicating means, and a plunger operable to eject the vaporized mixture of air and fuel from said chambervinto said combustion space.`

9. In an oil engine, the combination of a cylinder and a iston operable therein, an injector having lts discharge end subjected to the heat of combustion in the combustion space-and-provided with a vaporizing chamber, passage means in its discharge end to accommodate a charge of oil and conduct the charge of oil to said chamber, and restricted communicating means between said chamber and the combustion space; means for feeding a charge of oil to said passage means and thereby force the charge already therein into said chamber during the suction stroke of the piston, "and a plunger for ejecting the vaporized mixture of air and fuel from said chamber into the combustion space through said communicating means.

10. In an oil engine, the combination of a cylinder and a piston o erable therein, an injector having its disc arge end subjected to the heat of combustion in the combustion space and provided with a vaporizing chamber, passage means in its discharge end to accommodate a charge of oil and conduct the charge of oil to said chamber, and restricted communicating means between said chamber and the combustion space; means for feeding a charge of oil to said passage means and`thereby force the charge already therein into said chamber during the suction stroke of the piston, a plunger in said chamber and means for retracting said plunger while the charge of oil is being delivered into said chamber and for advancing said plunger during the compression stroke of the piston to eject the .entire vaporized mixture of air and fuel from said chamber into the combustion space through said restricted communicatengine, which consists in discharging a charge of oil into a vaporizing chamber at a point in the path of compressed air forced from the combustion space through re-A stricted openings into said vaporizing chamber during the compression stroke of the engine so as to entrain and vaporize the charge of oil in such vaporizing chamber, and then mechanically ejecting the entire mixture of air and fuel from the chamber through saidv restricted openings into the `combustion space.

12. The method of injecting la combustible charge of gasified oil and air into the combustion s ace of an internal combustion engine, whic consists in discharging oil durig the suction stroke into the vaporizing chamber at a point in the path of compressed air forced from the combustion space through short restricted openings into the vaporizing chamber during the compression stroke, retracting the plunger in said chamber during the suction stroke and then advancing the plunger to inject the entire combustible mixture of va orized oil and air 'through said restricte openings into the combustion` space during the combustion stroke of the engine.

13. The method of injecting a combustible charge into the combustion space of an internal combustion engine which consists in retracting the plunger in the vaporizing chamber during the suction stroke, delivering oil at the lower end of said chamber while the plunger is being retracted -from its seat on the lower end of said chamber so that air forced through the short restricted communicating openings between the chainber and the combustion space during the compression stroke vaporizes the oil in said chamber, and finally advancing the plunger to its seat during the combustion stroke to eject the entire vaporized mixture of air and fuel from said chamber through said communicating openings -into the combustion space.

14. The method of injecting a combusti-- ble charge into the combustion space of an internal combustionengine, which consists in depositing oil at the delivery end of the vaporizing chamber communicating with the combustion space through restricted opening, retracting the plunger in said chamber while the oilv is being deposited and until the initial part of the compression stroke, and finally advancing said plunger by a rapid movement near the beginning of the combustion stroke of the engine to eject the entire vaporized mixture of air and fuel from said chamber into-said combustion space through said communicating restricted openings.

15.- The method of injecting a combustible charge of gasied oil and air into the combustion space of an internal /combustionV engine, Awhich consists in delivering one chargeof oil to'lpassag'e means, subjected to the heat of combustion, to discharge the preheated charge of oil already therein into the path of heated compressed air orced'from the combustion 'space through .restricted openings into a vaporizing chamber and finally ejecting the gasiied ,mixture of oil and air from said chamber intosaid com--` bustion space .through said restricted open-- ings by aplungerin -said vaporizing cham# 16. Themethod of injecting' a combustible 'charge offgasified oil'and air intov the corn'-- bustionvspace ofi' an internal combustion engine, lwhich consists -'in delivering one charge ofoil to assage means, subjected to theheat of combustion, to dischargevduring the suction strokeof'the engine the pre-- heated charge of oil'already therein into v'the discharge vend of 'a vaporizingf-chamber f where it is in the path of heated compressed airp forced from the combustion space .throu` .i restricted'openings during' the compression stroke of the piston, retracting the plunger-.in said, chamber when the charge of oil jis discharged into. said chamber, and

H nallyndvanclng said plungerto' eject all vaporizing and injecting'device havingl its discharge end'subjected to the heat of compression and combustion injthe combustion space of the'cylinder and comprising chamber having a seat a't and'restricted openings in said discharge end, a plunger operable -in said'fchamber and adapted to seat againstvsaid-seatwhen the plunger is charge'of liquid fuel' through said heated end into the center of'said 'seat to form' a .pool over said restricted openings, so that the Vcharge of fuel. is` mixed -with the air forced from the combustion space intosaid chamber through said openings, means for retracting said plunger While the fuel is being deposited insaid chamber. and for advancingr said plunger to said seat .to eject the entire mixture of air and fuel from said chamber through said .openings into said combustion-space.

CLESSIE L. CUMMINS.

-fully advanced, means for conductinga 

